Dust Storms In The Sand Saltation And Suspended Load, The Numerical Simulation

A "Dual-Time"method is combined with Preconditioning method to solve two-dimensional viscous flow in low Mach number. LU-SGS implicit iterative method and JST central difference scheme are used to solve the two-dimensional Navier-Stokes equations with dual time step .The results of the numerical simulation carried on the viscous lid-driven cavity flow show that the dual time method used here can be applied to solve unsteady flows. The credibility of the results is proved by comparing with those results from other articles. The methods used here are proved be correct therefore are useful for the numerical simulation in unsteady incompressible flow with dual time step and preconditioning . Simulation to the sand saltation is carried. After that, the dual time method is used to simulate the flow over dunes. And then the results are used for solving transportation-dispersion equations to simulate the suspension of sands. Useful results are obtained and these results are the basis of further study if the dispersion of atmosphere and the forecast of the sand storms.